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  </script></head><body><div id="wrapper"><header><div id="header"><div><div><div class="logo noPrint"><a href="http://tomcat.apache.org/"><img alt="Tomcat Home" src="../images/tomcat.png"></a></div><div style="height: 1px;"></div><div class="asfLogo noPrint"><a href="http://www.apache.org/" target="_blank"><img src="../images/asf-feather.png" alt="The Apache Software Foundation" style="width: 266px; height: 83px;"></a></div><h1>Apache Tomcat 8 Configuration Reference</h1><div class="versionInfo">
          Version 8.0.36,
          <time datetime="2016-06-09">Jun 9 2016</time></div><div style="height: 1px;"></div><div style="clear: left;"></div></div></div></div></header><div id="middle"><div><div id="mainLeft" class="noprint"><div><nav><div><h2>Links</h2><ul><li><a href="../index.html">Docs Home</a></li><li><a href="index.html">Config Ref. Home</a></li><li><a href="http://wiki.apache.org/tomcat/FAQ">FAQ</a></li><li><a href="#comments_section">User Comments</a></li></ul></div><div><h2>Top Level Elements</h2><ul><li><a href="server.html">Server</a></li><li><a href="service.html">Service</a></li></ul></div><div><h2>Executors</h2><ul><li><a href="executor.html">Executor</a></li></ul></div><div><h2>Connectors</h2><ul><li><a href="http.html">HTTP</a></li><li><a href="ajp.html">AJP</a></li></ul></div><div><h2>Containers</h2><ul><li><a href="context.html">Context</a></li><li><a href="engine.html">Engine</a></li><li><a href="host.html">Host</a></li><li><a href="cluster.html">Cluster</a></li></ul></div><div><h2>Nested Components</h2><ul><li><a href="cookie-processor.html">CookieProcessor</a></li><li><a href="credentialhandler.html">CredentialHandler</a></li><li><a href="globalresources.html">Global Resources</a></li><li><a href="jar-scanner.html">JarScanner</a></li><li><a href="jar-scan-filter.html">JarScanFilter</a></li><li><a href="listeners.html">Listeners</a></li><li><a href="loader.html">Loader</a></li><li><a href="manager.html">Manager</a></li><li><a href="realm.html">Realm</a></li><li><a href="resources.html">Resources</a></li><li><a href="sessionidgenerator.html">SessionIdGenerator</a></li><li><a href="valve.html">Valve</a></li></ul></div><div><h2>Cluster Elements</h2><ul><li><a href="cluster.html">Cluster</a></li><li><a href="cluster-manager.html">Manager</a></li><li><a href="cluster-channel.html">Channel</a></li><li><a href="cluster-membership.html">Channel/Membership</a></li><li><a href="cluster-sender.html">Channel/Sender</a></li><li><a href="cluster-receiver.html">Channel/Receiver</a></li><li><a href="cluster-interceptor.html">Channel/Interceptor</a></li><li><a href="cluster-valve.html">Valve</a></li><li><a href="cluster-deployer.html">Deployer</a></li><li><a href="cluster-listener.html">ClusterListener</a></li></ul></div><div><h2>web.xml</h2><ul><li><a href="filter.html">Filter</a></li></ul></div><div><h2>Other</h2><ul><li><a href="systemprops.html">System properties</a></li></ul></div></nav></div></div><div id="mainRight"><div id="content"><h2>The Channel Interceptor object</h2><h3 id="Table_of_Contents">Table of Contents</h3><div class="text">
<ul><li><a href="#Introduction">Introduction</a></li><li><a href="#Available_Interceptors">Available Interceptors</a></li><li><a href="#Static_Membership">Static Membership</a></li><li><a href="#Attributes">Attributes</a><ol><li><a href="#Common_Attributes">Common Attributes</a></li><li><a href="#org.apache.catalina.tribes.group.interceptors.DomainFilterInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.DomainFilterInterceptor Attributes</a></li><li><a href="#org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor_Attributes">org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor Attributes</a></li><li><a href="#org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor Attributes</a></li><li><a href="#org.apache.catalina.tribes.group.interceptors.TcpFailureDetector_Attributes">org.apache.catalina.tribes.group.interceptors.TcpFailureDetector Attributes</a></li><li><a href="#org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor Attributes</a></li><li><a href="#org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor Attributes</a></li></ol></li><li><a href="#Nested_Components">Nested Components</a><ol><li><a href="#StaticMember_Attributes">StaticMember Attributes</a></li></ol></li></ul>
</div><h3 id="Introduction">Introduction</h3><div class="text">
  <p>
  Apache Tribes supports an interceptor architecture to intercept both messages and membership notifications.
  This architecture allows decoupling of logic and opens the way for some very kewl feature add ons.
  </p>
</div><h3 id="Available_Interceptors">Available Interceptors</h3><div class="text">
   <ul>
    <li><code>org.apache.catalina.tribes.group.interceptors.TcpFailureDetector</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.NonBlockingCoordinator</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.OrderInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.SimpleCoordinator</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.StaticMembershipInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.TwoPhaseCommitInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.DomainFilterInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.FragmentationInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.GzipInterceptor</code></li>
    <li><code>org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor</code></li>
   </ul>
</div><h3 id="Static_Membership">Static Membership</h3><div class="text">
  <p>
   In addition to dynamic discovery, Apache Tribes also supports static membership, with membership verification.
   To achieve this add the <code>org.apache.catalina.tribes.group.interceptors.StaticMembershipInterceptor</code>
   underneath the <code>org.apache.catalina.tribes.group.interceptors.TcpFailureDetector</code> interceptor.
   Inside the <code>StaticMembershipInterceptor</code> you can add the static members you wish to have.
   The <code>TcpFailureDetector</code> will do a health check on the static members,and also monitor them for crashes
   so they will have the same level of notification mechanism as the members that are automatically discovered.</p>
   <div class="codeBox"><pre><code>     &lt;Interceptor className="org.apache.catalina.tribes.group.interceptors.StaticMembershipInterceptor"&gt;
       &lt;LocalMember className="org.apache.catalina.tribes.membership.StaticMember"
                  domain="staging-cluster"
                  uniqueId="{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,1}"/&gt;
       &lt;Member className="org.apache.catalina.tribes.membership.StaticMember"
                  port="5678"
                  securePort="-1"
                  host="tomcat01.mydomain.com"
                  domain="staging-cluster"
                  uniqueId="{0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}"/&gt;
     &lt;/Interceptor&gt;</code></pre></div>
</div><h3 id="Attributes">Attributes</h3><div class="text">

  <div class="subsection"><h4 id="Common_Attributes">Common Attributes</h4><div class="text">
   <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><strong><code class="attributeName">className</code></strong></td><td>
       Required, as there is no default
     </td></tr><tr><td><code class="attributeName">optionFlag</code></td><td>
       If you want the interceptor to trigger on certain message depending on the message's option flag,
       you can setup the interceptors flag here.
       The default value is <code>0</code>, meaning this interceptor will trigger on all messages.
     </td></tr></table>
  </div></div>

  <div class="subsection"><h4 id="org.apache.catalina.tribes.group.interceptors.DomainFilterInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.DomainFilterInterceptor Attributes</h4><div class="text">
   <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><strong><code class="attributeName">domain</code></strong></td><td>
       The logical cluster domain that this Interceptor accepts.
       Two different type of values are possible:<br>
       1. Regular string values like "staging-domain" or "tomcat-cluster" will be converted into bytes
       using ISO-8859-1 encoding.<br>
       2. byte array in string form, for example {216,123,12,3}<br>
     </td></tr></table>
  </div></div>
  <div class="subsection"><h4 id="org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor_Attributes">org.apache.catalina.tribes.group.interceptors.MessageDispatch15Interceptor Attributes</h4><div class="text">
   <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><strong><code class="attributeName">className</code></strong></td><td>
       Required, This dispatcher uses JDK 1.5 java.util.concurrent package
     </td></tr><tr><td><code class="attributeName">optionFlag</code></td><td>
       The default and hard coded value is <code>8 (org.apache.catalina.tribes.Channel.SEND_OPTIONS_ASYNCHRONOUS)</code>.
       The dispatcher will trigger on this value only, as it is predefined by Tribes.
       The other attributes are inherited from its base class <code>org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor</code>.
     </td></tr><tr><td><code class="attributeName">maxThreads</code></td><td>
       The maximum number of threads in this pool, default is 10.
     </td></tr><tr><td><code class="attributeName">maxSpareThreads</code></td><td>
       The number of threads to keep in the pool, default is 2.
     </td></tr><tr><td><code class="attributeName">keepAliveTime</code></td><td>
       Maximum number of milliseconds of until Idle thread terminates. Default value is 5000(5 seconds).
     </td></tr></table>
  </div></div>
  <div class="subsection"><h4 id="org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor Attributes</h4><div class="text">
   <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><strong><code class="attributeName">className</code></strong></td><td>
       Required, Same implementation as <code>MessageDispatch15Interceptor</code>, but with JDK 1.4 compliance.
     </td></tr><tr><td><code class="attributeName">optionFlag</code></td><td>
       The default and hard coded value is <code>8 (org.apache.catalina.tribes.Channel.SEND_OPTIONS_ASYNCHRONOUS)</code>.
       The dispatcher will trigger on this value only, as it is predefined by Tribes.
     </td></tr><tr><td><code class="attributeName">alwaysSend</code></td><td>
       What behavior should be executed when the dispatch queue is full. If <code>true</code> (default), then the message is
       is sent synchronously, if <code>false</code> an error is thrown.
     </td></tr><tr><td><code class="attributeName">maxQueueSize</code></td><td>
       Size in bytes of the dispatch queue, the default value is <code> 1024*1024*64 (64MB)</code> sets the maximum queue size for the dispatch queue
       if the queue fills up, one can trigger the behavior, if <code>alwaysSend</code> is set to true, the message will be sent synchronously
       if the flag is false, an error is thrown
     </td></tr></table>
  </div></div>
  <div class="subsection"><h4 id="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector_Attributes">org.apache.catalina.tribes.group.interceptors.TcpFailureDetector Attributes</h4><div class="text">
   <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><code class="attributeName">connectTimeout</code></td><td>
       Specifies the timeout, in milliseconds, to use when attempting a TCP connection
       to the suspect node. Default is 1000.
     </td></tr><tr><td><code class="attributeName">performSendTest</code></td><td>
       If true is set, send a test message to the suspect node. Default is true.
     </td></tr><tr><td><code class="attributeName">performReadTest</code></td><td>
       If true is set, read the response of the test message that sent. Default is false.
       <strong>Note: </strong>if <code>performSendTest</code> is false, this attribute will have no effect.
     </td></tr><tr><td><code class="attributeName">readTestTimeout</code></td><td>
       Specifies the timeout, in milliseconds, to use when performing a read test
       to the suspicious node. Default is 5000.
     </td></tr><tr><td><code class="attributeName">removeSuspectsTimeout</code></td><td>
       The maximum time(in seconds)  for remove from removeSuspects. Member of
       removeSuspects will be automatically removed after removeSuspectsTimeout.
       If a negative value specified, the removeSuspects members never be
       removed until disappeared really. If the attribute is not provided,
       a default of 300 seconds (5 minutes) is used.
     </td></tr></table>
  </div></div>
  <div class="subsection"><h4 id="org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor Attributes</h4><div class="text">
   <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><code class="attributeName">interval</code></td><td>
       If useThread == true, defines the interval of sending a ping message.
       default is 1000 ms.
     </td></tr><tr><td><code class="attributeName">useThread</code></td><td>
       Flag of whether to start a thread for sending a ping message.
       If set to true, this interceptor will start a local thread for sending a ping message.
       if set to false, channel heartbeat will send a ping message.
       default is false.
     </td></tr></table>
  </div></div>
  <div class="subsection"><h4 id="org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor_Attributes">org.apache.catalina.tribes.group.interceptors.ThroughputInterceptor Attributes</h4><div class="text">
   <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><code class="attributeName">interval</code></td><td>
       Defines the interval in number of messages when we are to report the throughput statistics.
       The report is logged to the <code>org.apache.juli.logging.LogFactory.getLog(ThroughputInterceptor.class)</code>
       logger under the <code>INFO</code> level.
       Default value is to report every <code>10000</code> messages.
     </td></tr></table>
  </div></div>
</div><h3 id="Nested_Components">Nested Components</h3><div class="text">

  <div class="subsection"><h4 id="StaticMember_Attributes">StaticMember Attributes</h4><div class="text">
    <p><b>LocalMember:</b> <br>
    Static member that is the local member of the static cluster group.
    </p>
    <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><strong><code class="attributeName">className</code></strong></td><td>
        Only one implementation available:<code>org.apache.catalina.tribes.membership.StaticMember</code>
      </td></tr><tr><td><code class="attributeName">port</code></td><td>
        There is no need to set.
        The value of this attribute inherits from the cluster receiver setting.
      </td></tr><tr><td><code class="attributeName">securePort</code></td><td>
        There is no need to set.
        The value of this attribute inherits from the cluster receiver setting.
      </td></tr><tr><td><code class="attributeName">host</code></td><td>
        There is no need to set.
        The value of this attribute inherits from the cluster receiver setting.
      </td></tr><tr><td><code class="attributeName">domain</code></td><td>
        The logical cluster domain for that this static member listens for cluster messages.
        Two different type of values are possible:<br>
        1. Regular string values like "staging-domain" or "tomcat-cluster" will be converted into bytes
        using ISO-8859-1 encoding.
        2. byte array in string form, for example {216,123,12,3}<br>
      </td></tr><tr><td><strong><code class="attributeName">uniqueId</code></strong></td><td>
        A universally uniqueId for this static member.
        The values must be 16 bytes in the following form:<br>
        1. byte array in string form, for example {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}<br>
      </td></tr></table>

    <p><b>Member:</b> <br>
    Static member that add to the static cluster group.
    </p>
    <table class="defaultTable"><tr><th style="width: 15%;">
          Attribute
        </th><th style="width: 85%;">
          Description
        </th></tr><tr><td><strong><code class="attributeName">className</code></strong></td><td>
        Only one implementation available:<code>org.apache.catalina.tribes.membership.StaticMember</code>
      </td></tr><tr><td><strong><code class="attributeName">port</code></strong></td><td>
        The port that this static member listens to for cluster messages
      </td></tr><tr><td><code class="attributeName">securePort</code></td><td>
        The secure port this static member listens to for encrypted cluster messages
        default value is <code>-1</code>, this value means the member is not listening on a secure port
      </td></tr><tr><td><strong><code class="attributeName">host</code></strong></td><td>
        The host (or network interface) that this static member listens for cluster messages.
        Three different type of values are possible:<br>
        1. IP address in the form of "216.123.1.23"<br>
        2. Hostnames like "tomcat01.mydomain.com" or "tomcat01" as long as they resolve correctly<br>
        3. byte array in string form, for example {216,123,12,3}<br>
      </td></tr><tr><td><code class="attributeName">domain</code></td><td>
        The logical cluster domain for that this static member listens for cluster messages.
        Two different type of values are possible:<br>
        1. Regular string values like "staging-domain" or "tomcat-cluster" will be converted into bytes
        using ISO-8859-1 encoding.<br>
        2. byte array in string form, for example {216,123,12,3}<br>
      </td></tr><tr><td><strong><code class="attributeName">uniqueId</code></strong></td><td>
        A universally uniqueId for this static member.
        The values must be 16 bytes in the following form:<br>
        1. byte array in string form, for example {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}<br>
      </td></tr></table>
  </div></div>
  

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